import turtle as l
import random
pos = [-25, 260]

def po():
    l.clear()
    l.colormode(255)
    l.up()
    l.goto(pos)
    l.down()
    pos[1]-=20
    r = random.randint(0, 255)
    g = random.randint(0, 255)
    b = random.randint(0, 255)
    l.fillcolor(r, g, b)
    l.begin_fill()
    for i in range(5):
        l.fd(50)
        l.right(144)
    l.end_fill()
    l.ontimer(po,900)
l.tracer(False)
po()
l.done()